Allen Costo
Biographical information
Physical description
Other information
Functionssecret agent
AlliesCosto family, Eve, and Rebecca Climant

Allen Costo is one of the main characters of the Spy Mistake series. He is the younger brother of Otis Costo and Austin Hastings.

History and AppearancesEdit

Allen is an extreme, lovable, dangerous and explosive boy who barely gets good grades. He once was kidnapped when he was younger but then escaped with his smartnest or television watching he calls it. He can also be rude and use foul language towards his enemies or family members. In the second series of Spy Mistake, he is described as a changed boy because of his now attitude.

Underneath the GraveEdit

Allen Costo"s first appearance in the series was in the first book, where he and his brother Otis attended their father's funeral. He was taken out of the ceremony by an interruption by Mr.Crestor. It is stated that Allen was as scared as his brother when this happened because Mr.Crestor pretended to be a cop. After he and the man spoke, he along with Otis, witnessed the kidnapping of Mr.Crestor and then set out to find him after seeing that two things had fell out of his pockets. A permission form for the MSA and Robert Costo's wallet. He was next seen in the Montreal Café where he was attacked by The Nine men. He was shot in the shoulder by a poison bullet after meeting, Wickledon, the gadgeteer of MSA. Wickledon saved Allen's life. After the mayhem, him, Otis, Rebeca, Wickledon and Sabrina went to the MSA HQ which was located in the mall. While in the walls of the mall going towards the headquarters, they were attacked by The Nine men and General Gilbert. They won the fight and made there way up to the HQ into Mr.Crestor's office where the army awaited them. Somehow they all escaped and found Sabrina. After they returned to the MSA and were captured by Anthony Han and his army, The Nine men. They were all tied up and then almost blowed up in the MSA HQ. After Allen and Rebeca began dating and Mr.Crestor pretended to erase the brother's memory with a pen flashlight.


Allen appeared in this book also.

Cousin or FoeEdit

Allen appeared in this book too and was shot in the knee cap. The rest is not known because this book was lost

The Final BlowEdit

Allen also appeared in this book.

The Holocaust (Part 1)Edit

Allen appears in this book too.

The Holocaust (Part 2)Edit

Allen has appeared in this book.

Bad InkEdit

Allen does appear in this book but has so little lines.

Friends and FamilyEdit

Otis Costo

Sabrina Rox


Linda Costo

Jonah Hill/ Spy Kid

Robert Costo ( deseased)

Wickledon ( deceased)

Agent One


The Nine men

Agent Two

The Black Belts


Steven Harper

General Gilbert ( deceased/ suspect to the death of Robert Costo as said in the first book)

The Recruitment

Central Intelligance Agency