Reaction here

 

I'm stumped. I understand that the methylphenyl group would be ortho-directing (because the para position is occupied) and the carbonyl group is meta-directing, so I know where the substitution will occur. I'm just stumped as to what the electrophile is and how it will attach. Help please?

You have an alkyl chloride and a Lewis acid catalyst. Have a think about the mechanism for electrophilic substitution of chloride onto an aromatic ring using Cl2 and the same catalyst.

 

This reaction is actually a name reaction. Hint: it comes in the form of acylation or alkylation.