The only thing I'm finding with a fast google (my very best friend for online info) suggests unprofessionalism. One, Cheryl McCarthy Literary Agency's email is a hotmail account, not a business-dedicated email. Two, the only screenplay or novel mentioned in connection with Cheryl McCarthy Literary Agency is a self-published one by Arthur Ellis, using AuthorHouse. For this, no agent is necessary, and self-publishing is not the advice a competent agent would provide. There's some suggestion that she may be representing a screenwriter named Charlie Mezzano.
What there's not is any indication that the agency has ever sold a screenplay. Since a poor agent is worse than no agent, unless you can find out more, including multiple sales that were completed, I'd stay away.
Maryn, wishing she had better news